package com.lanqiao.tree;

public class BinaryTreeDemo {

	public static void main(String[] args) {
		//创建一棵二叉树
		BinaryTree binaryTree = new BinaryTree();
		//创建需要的结点
		HeroNode root = new HeroNode(1, "宋江");
		HeroNode node2 = new HeroNode(2, "吴用");
		HeroNode node3 = new HeroNode(3, "卢俊义");
		HeroNode node4 = new HeroNode(4, "林冲");
		HeroNode node5 = new HeroNode(5, "关胜");
		
		//手动创建二叉树
		root.setLeft(node2);
		root.setRight(node3);
		node3.setRight(node4);
		node3.setLeft(node5);
		binaryTree.setRoot(root);
		
		//测试
//		System.out.println("前序遍历！");
//		binaryTree.preOrder();
//		System.out.println("中序遍历！");
//		binaryTree.infixOrder();
//		System.out.println("后续遍历！");
//		binaryTree.postOrder();
//		
//		System.out.println();
//		System.out.println("前序查找");
//		HeroNode resNode = binaryTree.preOrderSearch(5);
//		System.out.println(resNode);
//		System.out.println("中序查找");
//		HeroNode resNode1 = binaryTree.infixOrderSearch(5);
//		System.out.println(resNode1);
//		System.out.println("后序查找");
//		HeroNode resNode2 = binaryTree.postOrderSearch(5);
//		System.out.println(resNode2);
		
		System.out.println("删除前，前序！");
		binaryTree.preOrder();
		System.out.println("删除后，前序！");
		binaryTree.delNode(3);
		binaryTree.preOrder();
	}

}
//定义一棵二叉树
class BinaryTree {
	private HeroNode root;
	
	public void setRoot(HeroNode root) {
		this.root = root;
	}
	
	//删除结点
	public void delNode(int no) {
		if (root != null) {
			if (root.getNo() == no) {
				root = null;
			}else {
				root.delNode(no);
			}
		}else {
			System.out.println("空树！");
		}
	}
	
	//前序遍历
	public void preOrder() {
		if (this.root != null) {
			this.root.preOrder();
		}else {
			System.out.println("当前二叉树为空！");
		}
	}
	
	//中序
	public void infixOrder() {
		if (this.root != null) {
			this.root.infixOrder();
		}else {
			System.out.println("当前二叉树为空！");
		}
	}
	
	//后续
	public void postOrder() {
		if (this.root != null) {
			this.root.postOrder();
		}else {
			System.out.println("当前二叉树为空！");
		}
	}
	
	//前序遍历查找
	public HeroNode preOrderSearch(int no) {
		if (root != null) {
			return root.preOrderSearch(no);
		}else {
			return null;
		}
	}
	
	//中序
	public HeroNode infixOrderSearch(int no) {
		if (root != null) {
			return root.infixOrderSearch(no);
		}else {
			return null;
		}
	}
	
	//后续
	public HeroNode postOrderSearch(int no) {
		if (root != null) {
			return root.postOrderSearch(no);
		}else {
			return null;
		}
	}
}

//先创建HeroNode结点
class HeroNode {
	private int no;
	private String name;
	private HeroNode left;
	private HeroNode right;
	
	public HeroNode(int no, String name) {
		this.no = no;
		this.name = name;
	}

	public int getNo() {
		return no;
	}

	public void setNo(int no) {
		this.no = no;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public HeroNode getLeft() {
		return left;
	}

	public void setLeft(HeroNode left) {
		this.left = left;
	}

	public HeroNode getRight() {
		return right;
	}

	public void setRight(HeroNode right) {
		this.right = right;
	}

	@Override
	public String toString() {
		return "HeroNode [no=" + no + ", name=" + name + "]";
	}
	
	//递归删除结点
	//1. 如果删除的结点是叶子节点，则删除该节点
	//2. 如果删除的结点是非叶子节点，则删除该子树
	public void delNode(int no) {
		if (this.left != null && this.left.no == no) {
			this.left = null;
			return;
		}
		if (this.right != null && this.right.no == no) {
			this.right = null;
			return;
		}
		if (this.left != null) {
			this.left.delNode(no);
		}
		if (this.right != null) {
			this.right.delNode(no);
		}
	}
	
	//前序遍历
	public void preOrder() {
		System.out.println(this);//先输出父节点
		//递归左子树
		if (this.left != null) {
			this.left.preOrder();
		}
		//递归右子树
		if (this.right != null) {
			this.right.preOrder();
		}
	}
	
	//中序遍历
	public void infixOrder() {
		//递归左子树
		if (this.left != null) {
			this.left.infixOrder();
		}
		//输出父节点
		System.out.println(this);
		//递归右子树
		if (this.right != null) {
			this.right.infixOrder();
		}
		
	}
	
	//后续遍历
	public void postOrder() {
		//递归左子树
		if (this.left != null) {
			this.left.postOrder();
		}
		//递归右子树
		if (this.right != null) {
			this.right.postOrder();
		}
		//输出父节点
		System.out.println(this);
	}
	
	//前序遍历查找
	public HeroNode preOrderSearch(int no) {
		//比较当前结点是不是
		if (this.no  == no) {
			return this;
		}
		//判断当前结点的左子节点是否为空，不为空，就递归
		HeroNode resNode = null;
		if (this.left != null) {
			resNode = this.left.preOrderSearch(no);
		}
		//说明在左边找到了
		if (resNode != null) {
			return resNode;
		}
		//判断当前结点的右子节点是否为空，不为空，就递归
		if (this.right != null) {
			resNode = this.right.preOrderSearch(no);
		}
		return resNode;
	}
	
	//中序遍历查找
	public HeroNode infixOrderSearch(int no) {
		//当前结点的左子节点是否为空，不为空，递归查找
		HeroNode resNode = null;
		if (this.left != null) {
			resNode = this.left.infixOrderSearch(no);
		}
		if (resNode != null) {
			return resNode;
		}
		if (this.no == no) {
			return this;
		}
		//右递归
		if (this.right != null) {
			resNode = this.right.infixOrderSearch(no);
		}
		return resNode;
	}
	
	//后续查找
	public HeroNode postOrderSearch(int no) {
		HeroNode resNode = null;
		if (this.left != null) {
			resNode = this.left.postOrderSearch(no);
		}
		if (resNode != null) {
			return resNode;
		}
		if (this.right != null) {
			resNode = this.right.postOrderSearch(no);
		}
		if (resNode != null) {
			return resNode;
		}
		if (this.no == no) {
			return this;
		}
		return resNode;
	}
}